Surgical instrument for deploying a prosthesis

ABSTRACT

The present invention relates to a surgical instrument ( 1 ) for deploying a prosthesis ( 200 ) and includes a first layer and second layer assembled together so as to define an internal space accessible to said surgical instrument ( 1 ) by means of an opening provided in said first layer, said surgical instrument including at least one sheet ( 2 ) made of a flexible resilient material, said sheet continuously overlapping itself one or more times so as to define a plurality of levels forming a spiral ( 3 ). The invention also relates to a kit including such a surgical instrument and such a prosthesis.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/119,581 filed May 27, 2011, now U.S. Pat. No. 8,808,315, which is aNational Stage Application of PCT/FR2009/051749 filed Sep. 17, 2009,which claims benefit of U.S. Provisional Application No. 61/097,986filed Sep. 18, 2008, and the disclosures of each of the above-identifiedapplications are hereby incorporated by reference in their entirety.

The present invention relates to a surgical instrument making itpossible to place a prosthesis, in particular for covering hernias, aswell as a kit comprising this surgical instrument and this prosthesis.

The abdominal wall in humans is made up of fats and muscles connected toeach other by fascias. A break in continuity can occur at the fascias,allowing part of the peritoneum to pass, which then constitutes a sac,or a hernia, containing either fat or part of the intestines. Hernias orincisional hernias (hernia occurring on a surgical parietal scar)manifest themselves by a protuberance on the surface of the skin and arequalified as umbilical or inguinal hernias or incisional hernias, forexample, depending on where they are located.

The most traditional method for repairing a hernia involves placingstressed suture threads. However, this type of repair causes pain forthe patient and, due to the significant stresses, involves anon-negligible risk of tearing of muscles and fascia by the suturesand/or a recurrence of the hernia.

In order to minimize the risks of recurrence, surgeons frequently usethe placement of a synthetic lattice prosthesis that replaces orstrengthens the weakened anatomical tissues without requiring that theedges of the damaged tissues be brought together. However, such aprosthesis is subject to an abdominal pressure that tends to expel ittowards the outside. Yet the effectiveness of the prosthesis, andtherefore the minimization of the risks of recurrence, depend in largepart on the fixing thereof. First, the spreading out of the prostheses,which are often flexible, is difficult, such that they tend to formfolds on the abdominal wall. The absence of complete spreading outcauses a risk of engagement of the peritoneal sac and increases thechances of recurrence. It is therefore crucial for the surgeon to ensurethat no part of the prosthesis is folded and that no viscus or any partof the intestines is inserted between the prosthesis and the abdominalwall. Then, poor positioning of the sutures or poor fixing of theprosthesis risks distorting the latter and creating stresses.

The present invention aims to propose a surgical instrument making itpossible to facilitate the spreading out and fixing of a prosthesis thatcan be used for the surgical treatment of hernias and making it possibleto resolve the aforementioned drawbacks, in particular, but notexclusively, for the surgical treatment of small hernias.

The present invention also relates to a surgical kit for the treatmentof a hernia of the abdominal wall.

In the present application, “prosthesis” refers to a biocompatiblemedical device that can be implanted in the human or animal body.

A first aspect of the invention relates to a surgical instrument fordeploying a prosthesis intended to fill in a hernial defect of theabdominal wall, said prosthesis including at least one first layer madefrom a biocompatible flexible material intended to be placed oppositethe abdominal wall, and at least one second layer made from abiocompatible flexible material intended to be placed opposite theabdominal cavity, said first and second layers being assembled togetherso as to define an internal space accessible to said surgical instrumentby means of an opening provided in said first layer, said surgicalinstrument including at least one sheet made of a flexible resilientmaterial, said sheet continuously overlapping itself one or more timesso as to define a plurality of levels (or layers) forming a spiral.

Due to the resilience of said sheet, the spiral is able to adopt asubstantially flat configuration, in which each level is in contact withthe adjacent level, corresponding to an idle configuration in which thespiral does not undergo significant stresses, or on the contrary adeployed configuration, in which no level is in contact with anotherlevel, corresponding to a configuration in which a force tending tospace the two ends of the spiral away from each other is exerted. Inthis application, we will also refer to the surgical instrumentaccording to the invention using the terms protective disc, or disc, orspiral.

Owing to the resilience of the material making up said sheet, the discor spiral has a spring effect: thus if, in its flat configuration, it isfolded by pressing it on itself while exerting pressure on its edges, ittends to return naturally to its flat configuration when the exertedpressure is released.

As will appear in the following description, the surgical instrumentaccording to the invention is intended to be introduced into theprosthesis within the internal space thereof, in order to facilitate theintroduction, placement and deployment of the prosthesis in theimplantation site. The surgical instrument must then be removed from theprosthesis once the latter is fixed to the implantation site.

In one embodiment of the invention, the upper end of the spiral (ordisc) comprises a removal tab. Thus, once the prosthesis is correctlydeployed and positioned, then fixed, the surgeon can remove the surgicalinstrument or disc from the prosthesis by pulling on the removal tab: hethen deploys the disc, which extends in the form of a spiral, and thesurgeon can then easily remove the disc by causing it to rotate arounditself, or more easily by exerting a simple upward linear traction onthe tab: given its shape and material, preferably having a low frictioncoefficient relative to the prosthesis, the spiral unwindsautomatically.

In one embodiment of the invention, the material making up said sheet isa polymer chosen from polypropylene, polyethylene,polytetrafluoroethylene (PTFE), and/or mixtures thereof, for examplehaving a low friction coefficient with the prosthesis to facilitate theremoval thereof.

The present invention also relates to a surgical kit for treating ahernia of the abdominal wall comprising:

-   -   a surgical instrument as described above;    -   and a prosthesis intended to fill in said defect, said        prosthesis comprising at least one layer of a biocompatible        flexible material intended to be placed opposite the abdominal        wall and at least one second biocompatible flexible material        intended to be placed opposite the abdominal cavity, said first        and second layers being assembled to each other so as to define        an open inner space using an opening formed in said first layer.

In one embodiment, the surgical kit according to the invention includesa plurality of centering threads intended to be connected to saidprosthesis around the perimeter of said opening. It is understood thatthe centering threads can be fixed to the prosthesis beforehand or thatsaid centering threads could be fixed later by the surgeon and/orremoved at the end of the operation.

In one embodiment of the surgical kit, at least one of the layers ofsaid prosthesis is made up of an arrangement of threads. Preferably,both layers are made up of an arrangement of threads.

In one embodiment of the invention, the second layer of said prosthesisof the kit is covered with an anti-adhesive coating on its face intendedto be placed opposite the abdominal cavity.

Within the meaning of this application, “anti-adhesive” refers to asmooth and non-porous biocompatible material or coating not offering anyroom for cellular recolonization.

The anti-adhesive coating according to the present invention makes itpossible to protect, at least during the initial scarring phase, thesecond layer of said prosthesis, i.e. it is not exposed to inflammatorycells, such as granulocytes, monocytes, macrophages, or multinucleargiant cells generally activated by the surgery. Indeed, at least duringthe initial scarring phase, the length of which can vary from about 5 to10 days, only the anti-adhesive coating is accessible by the differentfactors such as proteins, enzymes, cytokines, or inflammatory linecells, at the first textile portion.

In the event the anti-adhesive coating is made up of non-resorbablematerials, it thus protects the coated prosthesis layer before and afterimplantation, throughout the entire implantation time of the prosthesis.

Moreover, owing to the anti-adhesive coating, the fragile surroundingtissues such as the hollow viscera, for example, are protected, inparticular from the formation of unwanted severe post-surgical fibrousadhesions.

In the event the anti-adhesive material comprises a bioresorbablematerial, it is preferable to choose a bioresorbable material that doesnot resorb until several days have passed so that the anti-adhesivecoating can perform its function of protecting the intestine and thehollow organs during the days following the operation, and, until thecellular rehabilitation of the prosthesis in turn protects the fragileorgans.

Other features and advantages of the invention will appear upon readingthe following description of one particular embodiment, provided solelyas a non-limiting example, in which the prosthesis is a reinforcement ofthe abdominal wall.

FIG. 1 is a cross-sectional view of an abdominal median hernia orincisional hernia;

FIG. 2 is a perspective view of a prosthesis contained in the kitaccording to the present invention;

FIG. 3 is a cross-sectional illustration of the prosthesis of FIG. 2;

FIG. 4 is a cross-sectional diagrammatic illustration of the abdominalwall showing a repair of a hernia that has been done using a surgicalkit according to the present invention;

FIG. 5 is a perspective view of an embodiment of the surgical instrumentaccording to the invention, in its flat configuration;

FIG. 6 is a perspective view of the surgical instrument of FIG. 5, inits deployed configuration;

FIG. 7 is a perspective view of one embodiment of the kit according tothe invention, the surgical instrument being completely introduced intothe inner space of the prosthesis;

FIG. 8 is a diagrammatic cross-sectional illustration of the abdominalwall showing the introduction into the implantation site of the kit ofFIG. 7;

FIG. 9 is a perspective view of the kit of FIG. 7, once redeployed inthe implantation site (the latter not being shown);

FIG. 10 is a perspective view of the step for removing the surgicalinstrument from the prosthesis, once the latter is fixed in theimplantation site (the latter not being shown).

FIG. 1 shows a hernia 100 of the abdominal wall 101 that ischaracterized by a break in the continuity of the fascia 102 surroundingthe rectus muscles 103 and a passage of the peritoneum 104 forming asac, the hernial sac 105, which contains either fat (omentum) or part ofthe viscera 106, and then exerts pressure on the fatty tissues 107 andis flush with the skin 108. Hernia treatment 100 consists of replacingand maintaining the viscera 106 in the abdominal cavity 109.

FIGS. 2 and 3 show a prosthesis 200 able to fill in a hernial defect 100like that shown in FIG. 1, said prosthesis 200 comprising at least onefirst layer 201 of biocompatible flexible material intended to be placedopposite the abdominal wall 101 and at least one second layer 202 ofbiocompatible material intended to be placed opposite the abdominalcavity 109. Said first and second layers (201, 202) are assembled toeach other so as to define an inner space 203 open via an opening 204formed in said first layer 201 and extending to the assembly zone ofsaid first and second layers 201, 202.

In the illustrated example, the first layer 201 and the second layer 202are made up of arrangements of threads, such as tissues, non-wovens orknits, and they are assembled on their periphery by a seam 205. Thethreads forming the layers (201, 202) can be chosen among resorbableand/or non-resorbable threads 206. In the illustrated example, ananti-adhesive coating 206, which is preferably bioresorbable,advantageously covers the outer surface of the second layer 202 in orderto avoid in particular the formation of unwanted severe post-surgicalfibrous adhesions.

The prosthesis 200 of FIGS. 2 and 3 is intended to repair a hernia 100like that of FIG. 1, and must be positioned, after implantation, asshown in FIG. 4. In that figure, the prosthesis 200 is diagrammed, afterreduction of the hernial sac 105, as placed to fill in the hernialdefect 100: as shown in this figure, in which sutures (901; 903) arediagrammed, the surgeon has made an incision in the skin 108 and thefascia 102 to introduce the prosthesis 200 into the hernial defect; hehas then arranged the prosthesis 200, with its first layer 201 oppositethe abdominal wall 101 and its second layer 202 opposite the abdominalcavity 109; he has fixed the prosthesis 200 by suturing the layer 201 tothe fascia 102 and the peritoneum 104 using sutures 903, then he hasclosed the initial incisions of the fascia 102 and the skin 108 usingsutures 901.

During such an operation, the difficulty lies in the introduction anddeployment of the prosthesis 200, in particular its spreading out andplacement against the abdominal wall 101, whereas moreover the initialincisions in the skin 108 and the fascia 102 needing to be as small aspossible, the surgeon's workspace and visibility are particularlylimited.

FIGS. 5 and 6 show an embodiment of a surgical instrument 1 according tothe invention, said instrument 1 being particularly useful for theintroduction and deployment of the prosthesis 200 during the operationdescribed above.

As shown in FIGS. 5 and 6, the surgical instrument 1 according to theinvention comprises at least one sheet 2 made from a flexible andresilient material, said sheet 2 overlapping itself one or severaltimes, continuously, so as to define several layers or levels (a, b, c)forming a spiral 3. As shown in FIG. 6, the spiral 3 is finite (orlimited) and has two opposite ends, an upper end 3 a and a lower end 3b. Due to the resilience of said sheet 2, the spiral 3 can adopt asubstantially flat configuration, in which each level (a, b, c) is incontact with the adjacent level (a, b, c), corresponding to an idleconfiguration in which the spiral 3 does not undergo significantstresses: this configuration is shown in FIG. 5. Alternatively, thespiral 3 can adopt a deployed configuration, in which no level (a, b, c)is in contact with another level, corresponding to a configuration inwhich a force, for example exerted by the surgeon, tending to move thetwo ends (3 a, 3 b) of the spiral 3 away from each other is exerted:this configuration is shown in FIG. 6. The surgical instrument is thuscapable of adopting two configurations: a flat configuration, as shownin FIG. 5, and a deployed configuration, as shown in FIG. 6.

As appears in FIG. 5, in its flat configuration, the spiral 3, due tothe small thickness of the sheet 2, forms a flat disc, provided with acentral hole 3 c.

The material making up said sheet 2 is preferably a polymer of thepolypropylene, polyethylene, or polytetrafluorethylene (PTFE) type; sucha polymer makes it possible to give the sheet the necessary resilienceto go from its flat spiral configuration to its deployed spiralconfiguration. Moreover, as will appear from the continuation of thedescription, the material making up said sheet 2 allows the surgicalinstrument 1, when it is in its flat spiral configuration shown in FIG.5, to be folded in half on itself under the effect of a pressure exertedon two opposite edges, for example according to a fold corresponding toone of its diameters: in such a case, due to the resilience of the sheet2, the surgical instrument 1 tends to return naturally to its flatconfiguration when the exerted pressure is released.

The disc or surgical instrument 1 thus has properties of resilience(redeployment after folding), rigidity (maintenance of the prosthesisagainst the abdominal wall), flexibility (facilitating removal thereof):the surgical instrument 1 according to the invention also plays aprotective role, as will appear later, in the area of the seam 205 ofthe prosthesis, during fixing of the latter to the abdominal wall,against any perforations by the suture needles or the staplerinsertions.

As appears in FIG. 6, the upper end 3 a of the spiral (or disc) 3comprises a removal tab 4.

The surgical instrument 1 can be introduced extremely easily into aprosthesis 200 as shown in FIG. 2: indeed, to do so, one need only, byusing the spiral 3 of the sheet 2 in its deployed form as shown in FIG.6, introduce the lower end 3 b of the spiral 3 into the opening 204 ofthe prosthesis, then rotate the spiral 3 relative to the prosthesis 200by making the sheet 2 slide in the inner space 203 of the prosthesis200.

Preferably, the material making up the sheet 2 has a low frictioncoefficient relative to the prosthesis 200 to facilitate both itsintroduction into the prosthesis 200, and as will be seen later, itsremoval. For example, if the threads making up the prosthesis are madefrom polyester, or polypropylene, and the sheet 2 is made frompolypropylene, or polytetrafluoroethylene, the sheet 2 will slide easilyagainst the prosthesis 200 because polyester and polypropylene have alow friction coefficient relative to polypropylene andpolytetrafluoroethylene.

In this way, the sheet 2 can be introduced completely into the innerspace 203 of the prosthesis 200, as shown in FIG. 7. As appears in thatfigure, once the surgical instrument 1 is completely introduced into theprosthesis 200, the spiral 3 is replaced in its flat configuration(corresponding to FIG. 5), with the removal tab 4, situated at the upperend 3 a of the spiral 3, visible through the opening 204.

The kit 10 thus made up of the prosthesis 200 and the surgicalinstrument 1 completely introduced into the open space 203 of theprosthesis 200, is completely flat. Due to the resilience of the sheet 2forming the surgical instrument 1 and the natural flexibility of theprosthesis 200, the layers (201, 202) of which are arrangements ofthreads, the surgeon can grasp the kit 100 (prosthesis 200+instrument 1)and fold it in two, or even in four, as shown in FIG. 8, by exertingpressure on the edges of the kit 10 in order to introduce it into theimplantation site in the abdominal cavity 109 through the incisionsformed at the skin 108 and the fascia 102. Because it is folded onitself, the kit 10 takes up little space and is easily introduced intosmall incisions.

Once in the abdominal cavity 109, the kit 10 redeploys naturally, owingto the resilience of the sheet 2, which tends to return naturally to itsflat spiral position 3 (corresponding to FIG. 5). FIG. 9 shows the kit10, as redeployed in the abdominal cavity: in this figure, however, forclarity reasons, the implantation site has not been shown again. Owingto the presence of the surgical instrument 1, its shape and itsstructure, and in particular its resilient properties, the surgeon thenknows that the prosthesis 200 is completely deployed, and that its layer201 in particular is advantageously pressed against the fascia 102 ofthe abdominal wall, without forming folds that risk causing unfortunatesutures with fragile surrounding organs such as the viscera. The surgeoncan then suture the layer 201 of the prosthesis 200 to the fascia 102 ofthe abdominal wall, using a needle 11 and thread 12 for example, asshown in FIG. 9. He thus performs the sutures 903 shown in FIG. 4, onthe periphery of the prosthesis 200, thereby forming fastening means forfastening the prosthesis 200. Alternatively, the surgeon could use astapler, for example a laparoscopy stapler, and staples as fasteningmeans. During this operation, the surgical instrument 1 according to theinvention plays a protective role to protect the surrounding viscera, inparticular in the vicinity of the seam 205 of the prosthesis 200, byavoiding, due to the presence of the sheet 2 that forms a barrier, anyperforations of these viscera by the suture needles or the insertions bythe stapler.

During this operation, the surgeon can be assisted, to center the kit10, and therefore the prosthesis 200, on the defect to be filled in, bycentering threads 13, already bound, or that he has bound beforehand, tothe prosthesis 200 on the perimeter of the opening 204 thereof, as shownin FIG. 9. These centering threads 13 are preferably removed once theprosthesis 200 is attached.

Once the prosthesis 200 is thus attached, the surgeon can remove thesurgical instrument 1, by removing the prosthesis 200 through theopening 204: to that end, he pulls on the sheet 2 using the removal tab4, which he grasps easily through the opening 204, and he deploys thespiral 3 while making it rotate relative to the prosthesis 200, as shownin FIG. 10. The surgical instrument 1 is thus easily removed from theprosthesis 200, in particular when the friction coefficient of thematerial making up the sheet 2 is low relative to the prosthesis 200.

The surgeon then needs only close the initial incisions of the fascia102 and the skin 106 using sutures 901 as shown in FIG. 4.

The surgical instrument 1 according to the invention thus allows adeployment and spreading out of the prosthesis 200 that are as effectiveas possible during an operation to reduce a hernial defect. Inparticular, due to its spring effect and its ability to stiffen theprosthesis, the surgical instrument according to the invention makes itpossible both to reduce the space occupied by the prosthesis when it isintroduced into the implantation site, and to perform optimal pressingof the latter against the abdominal wall, thereby making it possible toavoid the formation of unwanted folds within the prosthesis.

The present invention also pertains to a method for treating orpreventing a hernia in the umbilical region, by using a prosthesis and asurgical instrument (or disc) as described above and comprising thefollowing steps:

-   -   One has a prosthesis and a surgical instrument (or disc or        spiral) as described above: in one embodiment of the invention,        the disc, in its flat configuration, is already housed in the        prosthesis; in another embodiment, the surgeon introduces the        disc, in its flat form, inside the prosthesis: the latter is        thus completely deployed and slightly stiffened by the sheet of        material making up the disc;    -   An incision is made on the abdominal wall at the hernial defect;    -   After treating the hernia, said prosthesis, in which the disc is        housed, is inserted into the incision by folding it by exerting        pressure on the edges of the disc;    -   Owing to its spring effect, the disc deploys in the abdominal        cavity, bringing about the spreading out of the prosthesis; said        prosthesis is positioned against the abdominal wall, centering        it on the defect, for example by pulling on the centering        threads of the prosthesis, the sheet of material of the disc        stiffening the prosthesis and pressing it against the abdominal        wall such that viscera are prevented from being inserted between        said prosthesis and the abdominal wall; a correct spreading out        of said prosthesis is thus ensured;    -   The prosthesis is fixed against the abdominal wall owing to        fastening means;    -   One then pulls on the removal tab situated at the upper end of        the spiral of the disc; in so doing, one deploys the spiral and        removes the disc by making it rotate slowly around itself.

The invention claimed is:
 1. A surgical instrument for deploying aprosthesis intended to repair a hernial defect comprising: at least onesheet made of a flexible resilient material, said sheet continuouslyoverlapping itself one or more times so as to define a plurality oflevels forming a spiral, wherein a central hole passes through saidplurality of levels and said spiral is configured to adopt an idleconfiguration in which the spiral is flat and the plurality of levelsare in contact with each other.
 2. The surgical instrument according tothe claim 1, wherein said spiral is able to further adopt a deployedconfiguration, in which none of the plurality of levels are in contactwith each other.
 3. The surgical instrument according to the claim 1,wherein said spiral includes a removal tab.
 4. The surgical instrumentaccording to the claim 3, wherein said removal tab is positioned on anupper end of said spiral.
 5. The surgical instrument according to claim4, wherein said removal tab extends over the central hole.
 6. Thesurgical instrument according to the claim 3, wherein said spiral canrotate around itself via the removal tab.
 7. The surgical instrumentaccording to claim 1, wherein the material of the sheet comprises abiocompatible polymer.
 8. The surgical instrument according to claim 1,wherein the material of the sheet is chosen from polypropylene,polyethylene, polytetrafluoroethylene, and mixtures thereof.
 9. Thesurgical instrument according to claim 1, wherein the material of thesheet comprises polypropylene.
 10. The surgical instrument according toclaim 1, wherein the material of the sheet comprises polyethylene. 11.The surgical instrument according to claim 1, wherein the material ofthe sheet comprises polytetrafluoroethylene.
 12. The surgical instrumentaccording to claim 1, wherein the spiral displays two overlappinglayers.
 13. The surgical instrument according to claim 1, wherein thespiral displays three overlapping layers.
 14. The surgical instrumentaccording to claim 1, wherein the sheet is configured to be removed fromthe prosthesis following deployment.